#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>

int switch_func(int result);

int main() {
    int result;

    printf("Input a number from 0 to 3:\n");
    scanf("%d", &result);

    int x = switch_func(result);

    printf("%d\n", x);

    return 0;
}

int switch_func(int result) {
    switch (result)
    {
    case 1:
        return result * 10;
    case 2:
        return result * 20;
    case 3:
        return result * 30;
    default:
        return 0;
    }
}